TY - JOUR
T1 - Structure-activity relationships of benzoxazolinones with respect to auxin-induced growth and auxin-binding protein
AU - Hoshi-Sakoda, Masako
AU - Usui, Kenji
AU - Ishizuka, Kozo
AU - Kosemura, Seiji
AU - Yamamura, Shosuke
AU - Hasegawa, Koji
N1 - Funding Information:
Acknowledgements-Weth ank SumitomoC hemicalsf or the supplyo f ‘H-NAA, Dr N. Mito (AgriculturalS cience Laboratory,S umitomoC hemicals)f or his valuables ug-gestionsa nd Prof. 1. Bruinsma,T he Netherlandsf or his valuablec ommentsT. his work was supportedin part by grants from the Ministry of Education, Science and Culture, Japan. The senior author thanks the Japanese Societyf or the Promotion of Sciencef or a fellowship.
PY - 1994
Y1 - 1994
N2 - The structure-activity relationships of the naturally occurring auxin-inhibiting substance, 6-methoxy-2-benzoxazolinone, isolated from maize shoots, and its artificial analogues with respect to auxin activity and membrane-bound auxin-binding protein, were studied. 6-Isobutoxy-2-benzoxazolinone strongly inhibited auxin (1-naphthylacetic acid, NAA)-induced growth of etiolated maize coleoptile segments. 6-Isopropoxy-2-benzoxazolinone, 6-ethoxy-2-benzoxazolinone and 6-methoxy-2-benzoxazolinone showed significant inhibitory activity. However, 2-benzoxazolin-one and 6-benzyloxy-2-benzoxazolinone did not inhibit auxin-induced growth. On the basis of these data, it seemed reasonable to assume that the auxin-inhibitory activity was enhanced by increasing the side chain length at position C-6 on the 2-benzoxazolinone, although the attachment of a ring at C-6 destroyed activity. Competition by benzoxazolinones with an alkoxy group at C-6 with 3H-NAA at auxin-binding protein(s) isolated from endoplasmic reticulum (ER) membrane of maize shoots showed a positive correlation with their physiological effects. However, since the inhibitory activity of the benzoxazolinones for auxin-receptor(s) binding was small compared with their physiological activity, the benzoxazolinones may contribute to inhibition of auxin-induced growth through interference with other auxin-receptors.
AB - The structure-activity relationships of the naturally occurring auxin-inhibiting substance, 6-methoxy-2-benzoxazolinone, isolated from maize shoots, and its artificial analogues with respect to auxin activity and membrane-bound auxin-binding protein, were studied. 6-Isobutoxy-2-benzoxazolinone strongly inhibited auxin (1-naphthylacetic acid, NAA)-induced growth of etiolated maize coleoptile segments. 6-Isopropoxy-2-benzoxazolinone, 6-ethoxy-2-benzoxazolinone and 6-methoxy-2-benzoxazolinone showed significant inhibitory activity. However, 2-benzoxazolin-one and 6-benzyloxy-2-benzoxazolinone did not inhibit auxin-induced growth. On the basis of these data, it seemed reasonable to assume that the auxin-inhibitory activity was enhanced by increasing the side chain length at position C-6 on the 2-benzoxazolinone, although the attachment of a ring at C-6 destroyed activity. Competition by benzoxazolinones with an alkoxy group at C-6 with 3H-NAA at auxin-binding protein(s) isolated from endoplasmic reticulum (ER) membrane of maize shoots showed a positive correlation with their physiological effects. However, since the inhibitory activity of the benzoxazolinones for auxin-receptor(s) binding was small compared with their physiological activity, the benzoxazolinones may contribute to inhibition of auxin-induced growth through interference with other auxin-receptors.
KW - Gramineae
KW - Zea mays
KW - antiauxin
KW - auxin-binding protein
KW - benzoxazolinone
KW - structure-activity relationships.
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U2 - 10.1016/0031-9422(94)85050-X
DO - 10.1016/0031-9422(94)85050-X
M3 - Article
AN - SCOPUS:0028002999
SN - 0031-9422
VL - 37
SP - 297
EP - 300
JO - Phytochemistry
JF - Phytochemistry
IS - 2
ER -